Battery backed RTC

[PaulB]

I need a battery backed RTC — similar to what desktop PCs have had for years.  For the Beaglebone Black Wireless, we use an external RTC with its own coin cell battery.  I’m confused as to whether the osd335x-SM can have its RTC battery backed without the whole system being run from battery.  If I have to go with an external RTC like I do now, is there any point in enabling the osd335x-sm’s RTC in a linux environment?

[Neeraj Dantu]

Due to the use of the TPS65217C PMIC within the OSD335x-SM, the RTC-only power mode is not available. There is an RTC within the OSD335x, however, the lowest power mode available is Deepsleep0. Please refer to our power application notes:

https://octavosystems.com/app_notes/osd335x-software-control-power-management/

https://octavosystems.com/app_notes/osd335x-sm-power-application-note/

for more information about low power modes and power budgeting.
The internal RTC module can still be used for timing functions, but not a low power mode.

• This reply was modified 5 years, 9 months ago by Neeraj Dantu.

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